Vibration welding is a manufacturing process than can be used to join two or more parts together, usually without the use of additional materials such as adhesives or fasteners. It can be used with plastic, metal, or other materials and generally involves applying mechanical vibrations to one or more of the parts to generate heat at the interface of the parts. The vibrations can be applied at frequencies and amplitudes sufficient to cause softening and/or melting of material at the interface. When the vibrations are halted, any softened or molten material can then cool and resolidify, forming a bond at the interface of the parts. Molten material formed during vibration welding and other types of welding operations can sometimes have unpredictable or undesirable flow characteristics.